[Recurrence pattern of pathological complete response after neoadjuvant chemoradiotherapy in locally advanced rectal cancer].

Patients with locally advanced rectal cancer who undergo neoadjuvant chemoradiotherapy may achieve pathological complete response (pCR). The incidence of recurrence is low among patients with pCR, there is still a lack of consensus on postoperative treatment and follow-up strategy. This review summarizes the recurrence patterns of patients with pCR, including distant metastasis rate, characteristics of distant metastasis time and location, local recurrence rate, and local recurrence time. The aim is to provide reference for the postoperative treatment and follow-up strategy of patients with pCR. Patients with pCR have a low recurrence rate, with infrequent local recurrence. Distant metastasis is the most common recurrence pattern, primarily in the lung and secondly in the regional lymph node. The time of recurrence is delayed which suggests the need for appropriate adjustments to follow-up strategy, extending the follow-up period, and placing emphasis on monitoring sites prone to recurrence.

[Study on the recurrence pattern of rectal cancer patients undergoing radical surgery after neoadjuvant chemoradiotherapy].

Objective: To analyze the recurrence pattern of rectal cancer patients with radical surgery after neoadjuvant chemoradiotherapy. Methods: The clinicopathological characteristics and follow-up information of rectal cancer patients with radical surgery after neoadjuvant chemoradiotherapy in the Cancer Hospital of the Chinese Academy of Medical Sciences from June 2004 to December 2017 were retrospectively collected. The recurrence pattern including the time and site was investigated. Results: The age of 537 patients was (55.5±11.7) years, of whom 361 were male (67.2%). The median follow-up time [M(Q1,Q3)] was 77.9 (64.5, 95.6) months. Moreover, 30.7% (165/537) of patients had distant metastasis or local recurrence; 26.8% (144/537) of patients had distant metastasis; 5.6% (30/537) of patients had local recurrence; 1.7% (9/537) of patients had both distant metastasis and local recurrence. In all the recurrent patients, 23.6% (39/165) were in the first year after surgery, followed by 27.3% (45/165) in the second year, 17.0% (28/165) in the third year, and 15.8% (26/165) after five years. According to the risk curve drawn by the life table, the highest metastasis risk of patients occurred in the second year after surgery, and the metastasis risk peak occurred again after more than five years. The lung was the most common metastatic organ, accounting for 47.9% (69/144), followed by the liver (18.8%, 27/144). The ratios of the recurrent patients in each ypTNM stage were 9.5% (8/84), 12.0% (12/100), 26.5% (41/155), 52.5% (104/198), respectively. The proportion of recurrent patients in tumor regression grade (TRG) 1-2 and TRG 3-5 patients were 19.2% (38/198) and 37.5% (127/339), respectively. Conclusions: The recurrence pattern of patients undergoing radical surgery after neoadjuvant chemoradiotherapy is mainly distant metastasis. The lung is the primary metastatic organ. The risk of distant metastasis and local recurrence is high in the first three years after surgery, and there is still high risk of recurrence after five years. For patients with ypTNM stage 2, 3 and TRG3-5, the postoperative adjuvant chemotherapy and long-term follow-up should be strengthened.

[A long-term follow-up study on recurrence and benefit of standardized postoperative chemotherapy of rectal cancer patients with complete pathological response after neoadjuvant chemoradiotherapy].

Objective: To analyze the clinicopathological factors affecting long-term disease-free survival and the characteristics of local recurrence or distance metastasis of rectal cancer patients with complete pathological response after neoadjuvant chemoradiotherapy. Methods: The clinicopathological data and follow-up information of patients with a complete pathological response of rectal cancer after neoadjuvant chemoradiotherapy in the Cancer Hospital of Chinese Academy of Medical Sciences from June 2004 to December 2019 were retrospectively collected. The clinicopathological factors affecting the long-term disease-free survival of patients were analyzed to build a prediction model of local recurrence and distant metastasis and to evaluate the benefits of postoperative chemotherapy. Results: The age of 108 patients was(56.3±11.6) years, of which 68 were males (63.0%); The median follow-up time was 79.9 (61.8, 112.6) months. There were 12 patients (11.1%) who had a local recurrence or distant metastasis. The 5-year disease-free survival rate was 91.1% with 9 patients who experienced recurrence. Multivariate Cox proportional hazards regression analysis showed that the maximum diameter of the residual tumor or scar (HR=8.41, 95%CI: 1.08-65.22, P=0.042) and the distance from the lower edge of the tumor to the anal margin before treatment (HR=4.54, 95%CI: 1.23-16.81, P=0.023) were independent risk factors affecting the prognosis. The prognosis of patients was stratified based on relevant factors. The 5-year cumulative disease-free survival rate of those patients receiving postoperative standardized chemotherapy was 92.0%, while for patients who did not receive or complete standardized chemotherapy, the 5-year cumulative disease-free survival rate was 82.3%. Conclusions: The maximum diameter of the residual tumor or scar and the distance from the lower edge of the tumor to the anal margin before treatment were independent risk factors affecting the prognosis of patients with a complete pathological response. Patients with independent risk factors could benefit from the standardized postoperative chemotherapy.

[Fibrocartilaginous mesenchymoma: a clinicopathological analysis of four cases].

Objective: To investigate the clinical, radiological, histological and molecular features and the differential diagnosis of fibrocartilaginous mesenchymoma (FM). Methods: Four cases of FM diagnosed in the Department of Pathology, the Sixth People's Hospital Affiliated to Shanghai Jiaotong University School of Medicine from 2020 to 2022 were analyzed. Related literature was also reviewed. Results: Case 1 was a 10-year-old girl with bone destruction in the sacrum and L5 articular processes revealed by CT scan. Case 2 was a 7-year-old girl with an aggressive lesion in her right distal ulna. Case 3 was an 11-year-old boy with a lesion in the metaphysis of his left proximal tibia. Case 4 was an 11-year-old boy with bone destruction in the distal portion of a radius. Microscopically, the four tumors all consisted of numerous spindle cells, hyaline cartilage nodules, and bone trabeculae. The hypocellular to moderately cellular spindle cell component contained elongated cells with slightly hyperchromatic, mildly atypical nuclei arranged in bundles or intersecting fascicles. Benign-appearing cartilaginous nodules of various sizes and shapes were scattered throughout the tumors. There were areas mimicking epiphyseal growth-plate characterized by chondrocytes arranged in parallel columns and areas of enchondral ossification. The stroma was rich in mucus in case 1. Mutation of GNAS and IDH1/IDH2 and amplification of MDM2 gene were not found in any of the three tested cases. Conclusions: FM is very rare and tends to affect young patients. It most frequently occurs in the metaphysis of long tubular bones, followed by the iliac-pubic bones and vertebrae. FM is characterized by a mixed population of spindle cells, hyaline cartilage nodules and trabeculae of bone, without specific immunophenotypes and molecular alternations. As a borderline, locally aggressive neoplasm, surgical removal with a wide margin is generally the treatment of choice for FM.

[Effect of dNLR and LIPI scores on the prognosis of elderly patients with non-surgical treatment of non-small cell lung cancer].

Objective: To investigate the effects of derived neutrophil to lymphocyte ratio (dNLR) and lung immune prognostic index (LIPI) score on the overall survival (OS) of non-surgical elderly non-small cell lung cancer (NSCLC) patients. Methods: Clinical and pathological data of NSCLC patients in Hebei General Hospital from January 2014 to June 2018 were collected retrospectively. The dNLR value was calculated based on the results of blood routine before treatment, and the optimal cut-off value of dNLR was obtained by ROC curve. The patients were divided into low dNLR level group and high dNLR level group based on the optimal dNLR cut-off value. The groups were classified as good, intermediate and poor based on the LIPI score consisting of lactate dehydrogenase (LDH) and dNLR tested before treatment. The Kaplan-Meier method and Log rank test were used for survival analysis, and the Cox risk proportional regression model was used for analysis of prognostic influences. Results: The area under the ROC curve for dNLR predicting prognosis in non-surgical elderly NSCLC patients was 0.591 (95% CI: 0.491, 0.692; P=0.093). The optimal cut-off value for dNLR predicting prognosis in elderly NSCLC patients was 2.515, with a sensitivity of 45.5% and a specificity of 81.8%. The gender, BMI, pathological type and degree of tumor differentiation were associated with dNLR levels (P<0.05). The median survival times were 16 and 10 months for patients in the low dNLR level group (dNLR<2.51) and high dNLR level group (dNLR≥2.51), respectively (P<0.001), and 15, 10 and 6 months for patients with good, intermediate and poor LIPI scores, respectively (P<0.001). The age, gender, smoking, pathological type, tumor differentiation, clinical stage, BMI, dNLR level, LDH level and LIPI scores were all associated with patient prognosis (P<0.05), and age≥76 years, tumor differentiation and clinical stage Ⅲ and Ⅳ were independent factors influencing patient prognosis (P<0.05). Conclusion: No matter what treatment measures are taken, dNLR level and LIPI score are related to patients' prognosis, and non-surgical elderly NSCLC patients with high dNLR level and poor LIPI score before treatment have worse prognoses.

[Sarcoma arising in fibrous dysplasia: a clinicopathological analysis].

Objective: To study the clinicopathologic characteristics and risk factors of sarcoma arising in fibrous dysplasia. Methods: A total of 18 cases were collected from January 2008 to July 2018 in Shanghai Jiaotong University Affiliated Sixth People's Hospital. The characteristics and the histologic type were retrospectively reviewed. IBM SPSS 19 was used for statistical analysis. Results: The male to female ratio of patients with fibrodysplastic sarcomatosis was 1.57∶1.00. The age of onset ranged from 24 to 87 years (mean 49 years). The long bones, especially the femur, were most frequently involved. Nine cases were osteosarcomas, three cases were high grade sarcoma and six cases were low grade sarcoma. Logistic regression analysis showed that age was an independent risk factor for sarcomatous change, compared with polyostotic or recurrent cases. Value of Wals was 13.61 (P<0.05), and odds ratio was 12.82,95% confidence interval was 3.31-49.70. Conclusions: Fibrodysplasia sarcomatosis is clinically nonspecific and the risk of sarcomatous changes increases approximately 12-fold when age of onset of fibrous dysplasia is over 40 years.

[A deep learning segmentation model for detecting caries in molar teeth].

This study aimed to build a home use deep learning segmentation model to identify the scope of caries lesions. A total of 494 caries photographs of molars and premolars collected via endoscopy were selected. Subsequently, these photographs were labeled by physicians and underwent segmentation training by using DeepLabv3+, and then verification and evaluation were performed. The mean accuracy was 0.993, the sensitivity was 0.661, the specificity was 0.997, the Dice coefficient was 0.685, and the intersection over union (IoU) was 0.529. Therefore, the present deep learning segmentation model can identify and segment the scope of caries.

[Efficacy and initial clinical evaluation of optical genome mapping in the diagnosis of structural variations].

To investigate the efficacy and value of optical genome mapping (OGM) in detecting chromosomal structural variations. In a clinical study about high-precision analysis of genomic structural variation for complex genetic diseases, a retrospective study was performed on the cases with karyotyping at the department of Obstetrics and Gynecology, and Endocrinology of Peking Union Medical College Hospital from January to December 2021. Ten cases with abnormal karyotype was detected by OGM. Partial cases were verified by fluorescence in situ hybridization (FISH), SNP array or CNV-seq. Results of ten cases, nine were detected with abnormality by OGM, including unbalanced chromosomal rearrangements (n=3), translocation (n=5) and paracentric inversion (n=1), and the results were in concordance with other standard assays. However, one case with breakpoint and reconnected at centromere has not been detected. In conclusion, ten samples were comprehensively analyzed by karyotyping, FISH, SNP array or CNV-seq, and OGM, and results demonstrated that optical genome mapping as a new technology can not only detect unbalanced rearrangements such as copy number variants as well as balanced translocations and inversions, but more importantly, it can refine breakpoints and orientation of duplicated segments or insertions. So it can contribute to the diagnosis of genetic diseases and prevent birth defect. However, the current technology is not yet capable of detecting breakpoints of balanced structural variations lying within unmapped regions.

[Eosinophilic vacuolated tumor of the kidney: clinicopathological and molecular characteristics].

Objective: To study the clinicopathological features, immunophenotype, molecular changes, differential diagnosis and prognosis of eosinophilic vacuolated tumor (EVT) of the kidney. Methods: Four cases were collected retrospectively from 2014 to 2020 at Ningbo Diagnostic Pathology Center. The clinicopathologic features and immunophenotypic profile were studied by light microscopy and immunohistochemistry. Targeted next-generation sequencing (NGS) panel was used to detect cancer-associated mutation. Follow-up and literature review were also performed. Results: Among the 4 patients studied,2 were males and 2 were females. The age of the patients ranged from 44 to 63 years (the mean age: 51 years).Tumor size ranged from 1.5 to 4.2 cm (mean: 2.3 cm). Microscopically, tumors were well-circumscribed, unencapsulated. Thick-walled vessels and entrapped renal tubules were found within or at the periphery of the tumors. The tumors were predominantly composed of nest pattern, and focal tubular pattern. The tumor cells exhibited abundant, eosinophilic, granular cytoplasm and conspicuous, large nucleoli. Prominent intracytoplasmic vacuoles were seen. These cytoplasmic vacuoles varied in size and frequently coalesced into a large space. Loose fibromatous or hyaline stroma was focally noted. Immunohistochemically, the tumor cells in all cases exhibited a CD117+/CK7-phenotype. All cases were positive for CD10 and p504s. MTOR, S6 and cathepsin K were positive in 4 cases. TFE3, CA9, Melan A and HMB45 were negative in all cases. SDHB retained expression. NGS demonstrated MTOR mutations in all cases, and TSC2 mutation in 2 cases. Conclusions: EVT is a rarely oncocytic renal tumor with unique morphology, immunohistochemical phenotype, molecular profile and an indolent behavior. Recognition of the characteristics of this novel but rare entity will allow for better classification of renal tumors.

[The prognostic impact of number-indexes of lymph nodes in stage N1c colorectal cancer patients].

Objective: To evaluate the impact of number-indexes of lymph nodes for prognostic stratification in stage N1c colorectal cancer (CRC) patients. Methods: The clinicopathologic data of CRC patients with stage pTxN1cM0 who initially underwent radical surgery in Cancer Hospital, Chinese Academy of Medical Sciences and the Surveillance, Epidemiology and End Results (SEER) database from January 2010 to December 2015 were retrospectively analyzed. A total of 1 165 patients with stage N1c were included in this study. Among them, 85 patients (including 54 males and 31 females) were from Cancer Hospital, Chinese Academy of Medical Sciences and their median age was 58 (range: 32-80) years; 1 080 patients (including 566 males and 514 females) were from the SEER database and their median age was 66 (range: 24-98) years. The prognostic significance of total number of lymph node (TLN), number of negative lymph node (NLN), and log odds of positive lymph nodes (LODDS) in stage N1c CRC patients were explored. Results: The optimal cut-off value of TLN or NLN was 13, and the optimal cut-off value of LODDS was -1.43. Among the 85 patients of Cancer Hospital, Chinese Academy of Medical Sciences, the 5-year overall survival (OS) rates of stage N1c1 (TLN or NLN≥13, 69 cases) and group LODDS1 patients (LODDS≤-1.43, 69 cases) were both 80.9%, which higher than that of stage N1c2 (TLN or NLN<13, 16 cases) and group LODDS2 (LODDS>-1.43, 16 cases) patients (both 53.3%, P=0.002); In the SEER cohort, the 5-year OS rates of stage N1c1 (837 cases) and group LODDS1 patients (LODDS≤-1.43, 837 cases) were both 64.7%, which higher than that of stage N1c2 (243 cases) and group LODDS2 (LODDS>-1.43, 243 cases) patients (both 52.2%, P<0.001). Both in the NCC cohort and SEER cohort, the results of Cox multivariate analysis all demonstrated that TLN or NLN<13 was the risk factor of OS of CRC patients with stage N1c (HR=3.794, 95%CI: 1.539-9.349, P=0.004; and HR=1.588, 95%CI:1.232-2.048, P<0.001; respectively); LODDS≤-1.43 was the independent protective factor of OS of stage N1c CRC patients (HR=0.264, 95%CI: 0.107-0.650; and HR=0.630, 95%CI: 0.488-0.812; respectively). Conclusions: TLN or NLN and LODDS were all independent prognostic factors of CRC patients with stage N1c. The clinicians could use TLN or NLN and LODDS for prognostic stratification and make the different adjuvant therapeutic schemes for CRC patients with stage N1c.

Moiré graphene nanoribbons: nearly perfect absorptions and highly efficient reflections with wide angles.

The strong absorption and reflection from atomically thin graphene nanoribbons has been demonstrated over the past decade. However, due to the significant band dispersion of graphene nanoribbons, the angle of incident wave has remained limited to a very narrow range. Obtaining strong absorption and reflection with a wide range of incident angles from atomically thin graphene layers has remained an unsolvable problem. Here, we construct a tunable moiré superlattice composed of a pair of graphene nanoribbon arrays to achieve this goal. By designing the interlayer coupling between two graphene nanoribbon arrays with mismatched periods, the moiré flat bands and the localization of their eigen-fields was realized. Based on the moiré flat bands of graphene nanoribbons, highly efficient reflection and nearly perfect absorption was achieved with a wide range of incident angles. Even more interesting, is how these novel phenomena can be tuned through the adjustment of the graphene's Fermi energy, either electrostatically or chemically. Our designed moiré graphene nanoribbons suggest a promising platform to engineer moiré physics with tunable behaviors, and may have potential applications in the field of wide-angle absorbers and reflectors in the mid-infrared region.

[Long-term conditional disease-free survival for rectal cancer patients underwent neoadjuvant chemoradiotherapy].

Objective: To explore the application value of the conditional disease-free survival (cDFS) analysis in predicting prognosis of stage-specific rectal cancer patients underwent neoadjuvant chemoradiotherapy (nCRT). Methods: Clinicopathologic data of 436 patients with rectal cancer received nCRT and radical operation in Cancer Hospital, Chinese Academy of Medical Sciences between January 2004 and December 2016 were retrospectively reviewed. With reference to conditional probability, the 3-year cDFS of patients at different ypTNM stage after completion of nCRT was estimated using the Kaplan-Meier method. Results: There were 66 patients of ypTNM stage 0 (pathological complete response), 87 patients of ypTNM stage Ⅰ, 135 patients of ypTNM stage Ⅱ and 148 patients of ypTNM stage Ⅲ. The 3-year accumulated DFS of patients with ypTNM stage 0, ypTNM stage Ⅰ, ypTNM stage Ⅱ, and ypTNM stage Ⅲ were 97.0%, 93.1%, 85.2%, and 64.2%, respectively. On the condition of postoperactive disease-free survival for 1 year, 2 years, 3 years, 4 years, and 5 years, the corresponding 3-year cDFS of patients at ypTNM stage 0 were 97.0%, 95.5%, 96.9%, 98.4%, 100.0%, respectively. The corresponding 3-year cDFS of patients at ypTNM Ⅲ were 68.2%, 79.3%, 86.3%, 92.1%, 96.4%, respectively. The more advanced ypTNM staging resulted in the more improvement of 3-year cDFS being acquired. Conclusion: cDFS is a better method to reflect the dynamic changes of the prognosis of rectal cancer patients with nCRT in different ypTNM stage, and it is useful to guide the clinicians to assess the prognosis and propose appropriate surveillance.

[The risk factors for regional lymph node metastasis of mismatch repair deficient colorectal cancer].

Objective: To explore the risk factors for regional lymph node (RLN) metastasis in colorectal cancer patients with mismatch repair deficiency (dMMR). Methods: The data of 357 dMMR colorectal cancer patients who underwent surgery in National Cancer Center from January 2012 to December 2016 was retrospectively analyzed. Univariate and multivariate analysis were used to identify the risk factors for RLN metastasis. Results: Among the 357 patients, 204 were male and 153 were female, 61.6% (220/357) lesion located in right half colon, while the other 16.2% (58/357) located in rectum. Univariate analysis showed that tumor size, differentiation, lymphovascular invasion, tumor deposit, postoperative pathologic T stage (pT), the number of negative lymph nodes and the expression of the MSH6 protein were significantly associated with RLN metastasis (P<0.05). All of the patients with well differentiation tumors (15 patients) or staged pT1 (13 patients) had no RLN metastasis. Multivariate analysis showed that tumor differentiation (OR=2.582, 95%CI=1.567-4.274, P<0.001), pT (OR=3.778, 95%CI=1.448-12.960, P=0.015) and the expression of MSH6 protein (OR=2.188, 95%CI=1.159-4.401, P=0.021) were independent risk factors for RLN metastasis. Conclusions: The postoperative pT stage, tumor differentiation and the expression of MSH6 protein are independent risk factors for RLN metastasis of dMMR colorectal cancer. Preoperative assessment of these factors may further improve the accuracy of predicting the risk of RLN metastasis.

[Advance on theoretical epidemiology models research of prevention and control of COVID-19].

COVID-19 has brought a significant impact to the global health system, and also opportunities and challenges to epidemiological researches. Theoretical epidemiological models can simulate the process of epidemic in scenarios under different conditions. Therefore, modeling researches can analyze the epidemical trend of COVID-19, predict epidemical risks, and evaluate effects of different control measures and vaccine policies. Theoretical epidemiological modeling researches provide scientific advice for the prevention and control of infectious diseases, and play a crucial role in containing COVID-19 over the past year. In this study, we review the theoretical epidemiological modeling researches on COVID-19 and summarize the role of theoretical epidemiological models in the prevention and control of COVID-19, in order to provide reference for the combination of mathematical modeling and epidemic control.

[Inflammatory myofibroblastic tumors of the urinary bladder: a clinicopathological study of ten cases].

0bjective To investigate the clinicopathological features,immunohistochemical phenotypes, molecular genetic alterations,diagnosis and differential diagnosis of inflammatory myofibroblastic tumor (IMT) of the urinary bladder. Methods: Ten cases of IMT of the urinary bladder (three cases at Ningbo Diagnostic Pathology Center from September 2011 to December 2020, five in-house diagnosed cases and two consultation cases at Shanghai Rui Jin Hospital from June 2011 to December 2020) were collected retrospectively. The clinicopathologic features and immunophenotypic profiles were studied by light microscopy and immunohistochemistry (EnVision method). The translocation of ALK gene was detected by fluorescence in situ hybridization (FISH). Results: Of the 10 patients, eight were male and two were female. The patients' age range was 16 to 62 years (median 36 years).The main clinical presentation was hematuria and urinary irritation. Three cases were located at the dome of the urinary bladder, four cases were in the left lateral wall and the remaining three cases were in the right lateral wall. The tumor size ranged from 1.5 cm to 8.5 cm. In eight cases, the tumors were mainly submucosal, and in some cases extending to the muscular layer of the urinary bladder. In two cases, the tumors were mainly located in the muscular layer and focally extended to the submucosa and adventitia. Histologically, four cases had the nodular fasciitis-like pattern, three cases had fibrohistiocytoma-like pattern, two cases had mixed histologic patterns and the remaining case showed leiomyosarcoma-like histologic features. Immunohistochemically, the tumor cells expressed SMA (10/10),calponin (9/10),desmin (6/10) and CKpan (9/10). Cytoplasmic staining for ALK1 and ALK (5A4) was detected in 7 of 10 cases and 8 of 10 cases, respectively. Nuclear and cytoplasmic staining for ALK (D5F3) was detected in 7 of 10 cases. Among eight cases with material available for FISH analysis, ALK rearrangement was present in five cases. Follow-up data were available in eight patients and none had local recurrence nor distant metastasis. Conclusion: IMT of the urinary bladder is an uncommon mesenchymal neoplasm with intermediate malignant potential.It has special clinicopathologic features, and a minority of cases have local tumor recurrence.

[Clinicopathological and prognostic features of young onset patients with middle-low rectal cancer received neoadjuvant chemoradiotherapy].

Objective: To explore the clinicopathological and prognostic features of young onset patients with middle-low rectal cancer who received neoadjuvant chemoradiotherapy (NCRT). Methods: After NCRT, a total of 441 patients with primary middle-low rectal cancer treated with radical surgery at the Cancer Hospital, Chinese Academy of Medical Sciences (CHCAMS) from January 2004 to December 2016 were included. According to the age of disease onset, the patients were divided into the young group (51cases) and the middle-old group (390 cases), and the clinicopathological characteristics and survival of these patients were analyzed. Results: In the young group, 68.6% of patients received radical surgery within 7 weeks after NCRT, which was higher than 52.8% in the middle-old group (P=0.047). The stage ypTNM Ⅲ in the young group was 51.0%, higher than 34.1% in the middle-old group (P=0.027). The stage ypN+ in the young group was 51.0%, higher than 34.1% in the middle-old group (P=0.047), The incidence of disease progression in the young group was 39.2%, higher than 25.1% in the middle-old group (P=0.049). The incidence of distant metastasis in the young group was 35.3%, higher than 21.5% in the middle-old group(P=0.044). Most cases of disease progression occurred in the first 3 years after surgery for the young group, especially in the second year after surgery, the incidence of disease progression in the young group was 55.0%, higher than 26.5% in middle-old group (P=0.025). The 3-year and 5-year disease-free survival (DFS) rates for the young group were 63.7% and 58.2%, lower than 81.0% and 74.3% in the middle-old group (P=0.016), respectively. The 3-year and 5-year overall survival in the middle-old group (OS) rates for the young group were 85.4% and 69.2%, lower than 93.6% and 84.1% in the middle-old group (P=0.033), respectively. The multivariate analysis showed that, response of primary tumor (HR=4.804, 95% CI: 1.360-16.973) and total number of dissected lymph nodes (HR=4.336, 95% CI: 1.739-10.809) in the young group were independent prognostic factors related to DFS. The total dissected number of lymph nodes(HR=3.295, 95% CI: 1.076-10.091)was an independent prognostic factor related to OS. In the middle-old group, response of primary tumor (HR=2.626, 95% CI: 1.354-5.091), ypTNM stage (ypTNM Ⅲ: HR=5.837, 95% CI: 2.968-11.479) and tumor location distance from the anal verge (HR=0.500, 95% CI: 0.308-0.812) were independent prognostic factors related to DFS. Lymphovascular invasion (HR=0.500, 95% CI: 0.308-0.812) and ypTNM stage (ypTNM Ⅲ: HR=16.322, 95% CI: 5.049-52.771) were independent prognostic factors related to OS. Conclusions: Young onset rectal cancer patients are associated with shorter operation time interval, advanced pathological stage and poorer prognosis. More intensive adjuvant treatment and post-treatment surveillance should be conducted to young onset rectal cancer with NCRT.

[Clinicopathological characteristics and prognostic analysis of patients with pathological complete response and near complete response after neoadjuvant treatment of rectal cancer].

Objective: To investigate the clinicopathological characteristics and prognosis of rectal cancer patients with pathological complete response and near complete response after neoadjuvant therapy. Methods: The clinicopathological data of patients who underwent neoadjuvant chemoradiotherapy plus radical surgery of rectal cancer in the Cancer Hospital of Chinese Academy of Medical Sciences from January 2004 to December 2016 were retrospectively collected. The clinicopathological characteristics and prognostic factor of patients with pathological complete response and near complete response were analyzed. Results: The clinical data of 142 patients were collected. There were 93 males and 49 females, aged from 24 to 81 years. The median disease-free survival was 53.9 months and the median overall survival was 55.0 months. Univariate analysis showed that the maximum diameter of scar or lesion, the status of lymph node metastasis and the distance between the lower edge of tumor and anal edge were associated with disease-free survival time; the maximum diameter of scar or lesion and the status of lymph node metastasis were associated with overall survival time. Multivariate Cox proportional hazards regression analysis showed that patients with scar or lesion diameter>3 cm (HR=4.406,95%CI:1.619-12.006), positive lymph node metastasis status (HR=4.102,95%CI:1.461-11.513) and tumor lower margin to anal margin distance ≤4 cm (HR=18.171,95%CI:2.357-140.073) had shorter disease-free survival time.The patients with scar or lesion diameter>3 cm (HR=8.573,95%CI:1.630-45.099) and lymph node metastasis status (HR=4.721, 95%CI:1.068-20.860) had shorter overall survival time. Conclusions: The overall prognosis of patients with pathological complete response or near complete response after neoadjuvant therapy for rectal cancer is better. The distance between the lower margin of the tumor and the anal edge, the status of lymph node metastasis and the maximum diameter of scars or lesion were the related factors affecting the prognosis of patients with rectal cancer.

[Clinicopathological features of notochordal tumors: a study of 48 cases].

Objective: To investigate the clinicopathological features, diagnosis and differential diagnosis of notochordal tumors. Methods: The clinical, radiologic and pathologic data of 48 notochordal tumors were collected from 2008 to 2019 at Shanghai Jiaotong University Sixth People's Hospital. Expression of cytokertin, S-100 protein, vimentin, brachyury and INI1 was detected by immunohistochemistry. The pathologic differential diagnoses and biologic behavior of various types of notochordal tumors were analyzed using the new standard in the 5th edition of WHO tumor classification. Results: Four cases of benign notochordal cell tumor were confined to vertebral body. Histopathologically, they lacked lobular architecture and extracellular myxoid matrix. The tumor cells were vacuolated and had centrally or peripherally located round to oval nuclei, with small nucleoli, without atypia, mimicking mature adipocytes. No mitotic figures were seen. Two cases of poorly differentiated chordoma, from patients aged 12 years and 21 years respectively, were located in cervical vertebra, and were composed of cohesive sheets or nests of epithelioid cells, with focal rhabdoid morphology. There was relatively abundant eosinophilic cytoplasm and scattered cytoplasmic vacuoles. The moderately pleomorphic nuclei were round to ovoid with vesicular chromatin and mitotic figures could be seen. Extracellular myxoid stroma was observed focally. Forty cases of conventional chordoma and two cases of extra-axis chordoma had similar histologic features. All 48 cases expressed cytokeretin, 45 cases expressed brachyury, and two poorly differentiated tumors showed loss of INI1/SMARCB1. Conclusions: There are four subtypes of chordomas: conventional, dedifferentiated, poorly differentiated and extra-axis. Chondroid chordoma is no longer thought to be a distinct entity. Each type has its unique clinicopathological characteristics. Brachyury is highly specific and sensitive for the diagnosis of various notochordal tumors. Poorly differentiated chordoma shows distinct clinicopathological features, including young age and loss of immunohistochemical expression of INI1/SMARCB1, and its diagnosis requires the combined detection of brachyury and INI1/SMARCB1.

Feasibility of the application of mixed reality in mandible reconstruction with fibula flap: A cadaveric specimen study.

BACKGROUND: In recent years, a new technology, mixed reality (MR), has emerged and surpassed the limitations of augmented reality (AR) with its inability to interact with hologram. This study aimed to investigate the feasibility of the application of MR in mandible reconstruction with fibula flap. METHODS: Computed tomography (CT) examination was performed for one cadaveric mandible and ten fibula bones. Using professional software Proplan CMF 3.0 (Materialize, Leuven, Belgium), we created a defected mandibular model and simulated the reconstruction design with these 10 fibula bones. The surgical plans were transferred to the HoloLens. We used HoloLens to guide the osteotomy and shaping of the fibular bone. After fixing the fibular segments using the Ti template, all segments underwent a CT examination. Before and after objects were compared for measurements of the location of fibular osteotomies, angular deviation of fibular segments, and intergonial angle distances. RESULTS: The mean location of the fibular osteotomies, angular deviation of the fibular segments, and intergonial angle distances were 2.11 ± 1.31 mm, 2.85°± 1.97°, and 7.24 ± 3.42 mm, respectively. CONCLUSION: The experimental results revealed that slight deviations remained in the accuracy of fibular osteotomy. With the further development of technology, it has the potential to improve the efficiency and precision of the reconstructive surgery.

Pelvic floor muscle training in the treatment of pelvic organ prolapse: A meta-analysis of randomized controlled trials. / Entrenamiento muscular del suelo pélvico en el tratamiento del prolapso de órganos pélvicos: un metaanálisis de ensayos controlados aleatorizados.

BACKGROUND: We aimed to assess the overall effect of pelvic muscle training (PFMT) on patients with pelvic organ prolapse (POP) based on eligible randomized controlled trials (RCT). METHODS: We searched the following databases, such as PubMed, Cochrane, and Embase, to identify eligible RCT based on the index words updated to December 2018. We also searched the publications related to the present study. Odds rations (OR), and mean difference (MD) along with 95% confidence interval (95% CI) were used to analyze the main outcomes. RESULTS: In this meta-analysis, 15 RCTs were included with a total of 1309 patients in the PFMT group and a total of 1275 patients in the control group. The overall results showed no significant difference in the incidence of add 2 POP-Q stages (RR: 0.55, 95%CI: 0.19-1.63), add 1 POP-Q stages (RR: 1.04, 95%CI: 0.69-1.57), no POP-Q stages change (RR: 0.94, 95%CI: 0.81-1.09), reduce 2 POP-Q stages (RR: 1.72, 95%CI: 0.79-3.76), self-reported same symptom change (RR: 0.70, 95%CI: 0.45-1.09), and self-reported worse symptom change (RR: 0.67, 95%CI: 0.22-2.03) between the 2groups. Besides, the incidence of reduce 1 POP-Q stages was significantly higher in the PFMT group than that of the control group (RR: 1.80, 95%CI: 1.20-2.69), and the PFMT significantly changed the self-reported symptoms with better outcomes when compared with the control group (RR: 2.90, 95%CI: 1.72-4.89). However, after the therapy, the PFMT group decreased the POP-SS (SMD: -0.24, 95%CI: -0.71-0.22), POPDI-6 (SMD: -0.14, 95%CI: -0.43-0.15), CRADI-8 (SMD: -0.03, 95%CI: -0.16-0.11), and UDI-6 (SMD: -0.17, 95%CI: -0.43-0.10) versus the control group, but without statistical significance. CONCLUSION: PMFT showed better effect in reducing 1 POP-Q stages, changing the self-reported symptoms with better outcomes, decreasing the score of POP-SS, POPDI-6, CRADI-8, and UDI-6 in women with POP versus the control group. However, more high-quality multicenter RCTs with a larger sample size are needed to confirm the present conclusions.